Structural reinforcement

ABSTRACT

In the general building and furniture industries, but notably in naval and yacht applications, the problem arises to reinforce, or to give other desired physical properties to materials, e.g. stone, used as linings or coverings. This problem is actually well solved for planar slabs. This invention discloses a method for solving the problem also in the case of non planar slabs, completing and giving general use and application to this technology. The invention teaches how to make it possible, by destructuring the reinforcing material, for it to match the form of the internal surface of the non planar stone slab to be reinforced; and, by restructuring and strongly binding it to the internal surface of the stone slab, to confer to the same the desired properties. For a lightweight and strong solution, a cellular structure (honeycomb) is recommended; for improving other physical properties, other materials like polyurethane foams can be used.

The invention presents a method for solving the problem of improving structural strength and other desired physical properties in non planar stone slabs.

TECHNICAL FIELD

The invention finds use and application in the field of producing stone linings and coverings mainly for the building and furniture industries.

BACKGROUND ART

The problem of increasing structural strength, or other desired physical properties, in planar stone slabs to be used as coverings or linings, is well known in the building (shipbuilding included) and furniture industries. It arises mainly from the necessity to improve the natural strength, or other physical properties, in stones used for some specific application; to reduce their specific weight; to reduce to a minimum the amount of precious or rare materials to be used as lining or covering.

The problem has found many different and pertinent solutions, for example by sticking, or otherwise connecting, to the internal face of a stone plate a plate of the material generally known as honeycomb, or a plate of polyurethane foam, or in general a plate possessing the desired structural properties, natural or artificially produced.

The honeycomb structure is a preferred choice where lightweight and high specific structural strength are required; where thermal and acoustical insulation are important, plastic foams are better used. All these materials are industrially produced in large quantities and with strict technical specifications, but only as planar slabs. Therefore the above mentioned problem is solved, and sometimes in a very satisfactory way, only in the case of planar stone slabs: in the case of non planar stone slabs, the solution is not available.

This invention gives a solution to the case of non planar stone slabs, greatly increasing, by that, the field of application of this type of improved materials, in the building and furniture industries, particularly in their advanced sectors, like naval and yacht furniture.

DISCLOSURE OF INVENTION

Conceptually: given a non planar stone slab (of which one face will be the external face of the finished product) and a planar slab of material (which we call reinforcing material, but which could possess also other desired physical properties), I propose to deform the planar slab of the reinforcing material in such a way that one of its faces (which we call here external) will acquire the geometry of the internal face of the non planar stone slab; this deformation will happen only if we act in such a way as to let the reinforcing material lose, at least partially or locally, the interconnection between its parts which gives to it his structural strength (this operation I call destructuring); the external surface of the so deformed reinforcing material will be made to adhere, in a stable and durable way, to the internal surface of the non planar stone slab; we will then restore, in a stable and durable way, the interconnection between the parts of the reinforcing material (this operation I call restructuring).

The result will be to give to a non planar stone slab nearly the same physical properties given to the reinforced planar stone slabs actually in use.

The above mentioned conceptual method will be better understood in the following examples.

BEST MODE FOR CARRYING OUT THE INVENTION

With a honeycomb slab the invention is applied by taking advantage from the fact that the two elements of which a honeycomb structure is made (central alveolar slab+external lining) show, each one of them, structural resistance, to compression and traction, only in one or two dimensions: each one of those elements, separately taken, can therefore be easily deformed or cut to adapt to many spatial forms: concave, convex, concave+convex, plane+concave, plane+convex. (This is obvious for the external lining, but also easy to do for the central alveolar slab, due to its spatial lamellar geometry and the material used for it: mainly some special aluminum alloy).

In other words, the elements of which a honeycomb structure is composed can be partially or totally disassembled; laid upon the surface of objects of various geometries in order to match their form; and made strongly connected to them. Once the previous external lining, or a new lining at his place, is again coupled, in a stable way, to the so deformed central alveolar slab, the resulting body will show again three dimensional properties of structural resistance. By connecting in a strong and durable way this body to the internal part of a non planar stone slab, the goal to reinforce it will be fully achieved and the invention applied.

Of course, the quality of the product must be good and consistent. This will be achieved by applying, to the process, standard methods and means, near as possible to the industrial procedures used in constructing reinforced planar stone slabs.

The best mode for carrying out the invention with a honeycomb structure in the case of a simple cylindrical geometry will be the following.

A hollow cylindrical sector of marble is designed to be used, together with other shells of the same form, to cover a raw pillar in the furniture of a luxury yacht; the shell is as thin as possible, for reasons of weight and, may be, also for sparing precious marble: in order not to fissure and rupture in handling, final finishing and use, the thin marble shell will need to be internally reinforced; this will be done with a strong but light structure.

Would the shell be not cylindrical but planar in shape, a planar honeycomb structure would be used at this end, as it is in fact usually done.

A planar honeycomb structure, modified as per this invention, will also be used, following this procedure: the marble shell, with its internal face row cut and the external surface finished or half finished (needing perhaps a final polishing), will be put in a oven, for a given time and with a given temperature, to perfectly dry; dried up and cooled down, on the internal surface of the shell an adhesive material (typically a structural epoxy resin) is applied; on the adhesive material is applied a tissue, (typically a plane woven glass fiber mat) imbibed with the same epoxy resin; a honeycomb plate, of the desired properties will be chosen in the market; will be stripped of one of its external coverings (exposing its open cells, and being made flexible by this operation); the open cells thus exposed on a face of the slab will be pressed on the mat internally lining the marble shell; the honeycomb slab will adhere to the mat and have the open side of the cells being wetted by the resin imbibing it; a uniform pressure is applied to hold firm the honeycomb slab against the marble shell (this is done, for example, by putting it inside a bag of non sticking material and air tight construction and sucking away the air from the same: due to the atmospheric pressure, the bag will press together the glued parts and held them firm); the resin will mature in an oven, at a precise temperature and timing.

A strong, light, stable reinforcement will be in this way applied in the internal face of the marble shell.

It will be noticed that, in the simple case of a cylindrical form, the original honeycomb planar slab, will need to be outstripped of only one of its external linings; the honeycomb material could be, in this case, as in fact sometimes is, ordered as such from its producer.

With other reinforcing materials, like for example polyurethane slabs, cuts and grooves of suitable depth will make them easy to be deformed and therefore adapted to the surface of non planar structures; and they will be restored in their strength by the same above described procedure.

Notice: this best mode for carrying out the invention is given as an example of a successful application and is not intended to limiting the scope or the substance of the invention, not from the viewpoint of the geometry, because the invention can be applied to any spatial form; nor to the materials to be reinforced or otherwise be given the desired physical properties, because any material can be reinforced, if the right reinforcing material is used; nor in terms of procedure, because different procedures can be chosen to the same end. 

1-10. (canceled)
 11. A method for producing and applying a reinforcing structure to thin stone slabs to be used as coverings or linings mainly in the building and furniture industries, said reinforcing structure being made to adapt to any non planar-form of the internal surface of the stone slab to be reinforced, said method being characterized by the use, as reinforcing structure, of a cellular slab of the type generally named honeycomb, made with strong but not brittle materials, like aluminum and aluminum alloys, reinforced plastics or other, and consisting of an internal cellular structure and two sheets for covering its faces; and in that it comprises the steps of separating, where necessary, the internal cellular structure of the said honeycomb from one or both of its covering sheets; restoring the bond between the said internal cellular structure and one or both of the covering sheets, once those materials are made to adapt to the form of the internal face of the stone slab to be reinforced.
 12. The method according to claim 11 characterized by the use, in restoring the said bond, of a binding material, for example a structural resin, to be applied, directly or indirectly between the stone slab and the honeycomb.
 13. The method according to claim 12 characterized by the use of a laminar product or a tissue, preferably a planar woven glass fiber mat, covered or impregnated by a binding material, preferably a structural resin, applied on one or both faces of the honeycomb slab.
 14. The method according to claim 13 characterized by the application of a given, uniform, external pressure, achieved preferably by pneumatic or hydraulic means, to the stone slab+honeycomb contraption, in order to hold firm in position its composing parts.
 15. The method according to claim 14 characterized by controlling time and temperature in the hardening process of the binding material or the structural resin, preferably by means of an oven, in order to optimize and guarantee the physical properties of the product.
 16. A method for producing and applying a reinforcing structure to thin stone slabs to be used as coverings or linings mainly in the building and furniture industries, said reinforcing structure being made to adapt to any non planar-form of the internal surface of the stone slab to be reinforced, said method being characterized by the use, as reinforcing structure, of a polyurethane slab or, in general a planar slab of solid material possessing thermal, acoustical or other desired physical properties, and in that it comprises the steps of applying on the said slab cuttings and grooves, on one or both faces, vertical or not, large and deep as necessary; said cuttings and grooves being such as to make it possible for the slab to adapt to the internal face of the stone slab to be reinforced, restoring, by means of a glue or a structural resin, the internal bond of the material severed by the cuts and grooves, once the same material is made to adapt to the internal face of the stone slab to be reinforced.
 17. The method according to claim 16 characterized by the possible use of a laminar product or a tissue, preferably a planar woven glass fiber mat, covered or impregnated by a binding material, or a structural resin, applied on one or both faces of the destructured slab made to adapt to the internal face of the stone slab to be reinforced.
 18. The method according to claim 17 characterized by the application of a given uniform external pressure, achieved preferably by pneumatic or hydraulic means, to the stone slab+reinforcing slab contraption, in order to hold firm in position its composing parts.
 19. The method according to claim 18 characterized by controlling time and temperature in the hardening process of the resin, preferably by means of an oven, in order to optimize and guarantee the properties of the product. 